Carbon-capping method and device



March 19, 1929. G. G. GUNDERSON CARBON CAPPING METHOD AND DEVICE Filed May 23, 1925 2 Sheets-Sheet 1 1720677 07 6: Gawderaon March 19, 1929. GUNDERSQN 1,706,155

CARBON CAPPING METHOD AND DEVICE Fi led May 23, 1925 2 Sheets-Sheet 2 HZ? /Z i 5 i I M I 4| 5 5 7 \9 1 lfik l A? L I l' 7 fl 4) 1 i w V I! R i I I Hjf fYUfYfiY:

' Eewye 6. Garza 676072,

Patented Mar. 19, 1929.

UNITED STATES unease PATENT GFFICE.

GEORGE G. GUNDERSON, OF MADISON, WISCONSIN, ASSIGNOR T FRENCH BATTER-Y COMPANY, OF MADiSON, WISCONSIN, A CORPORATEON SF VJ'ISCONSIIT CARBON-CAPPING METHOD AND DEVICE.

Application filed May 23, 1925.

This invention relates particularly to the capping of carbon pencils, or carbon rods, the capped carbon pencils being adapted to serve as electrodes for dry cells, particularly of the flash-light type As is known, carbon pencils of the character referred to are more or less brittle. Heretofore, it has been the practice to preparatorily form the brass caps and then apply them to the pencils.

In accordance with the present method, the

carbon pencil, suitably supported, serves as a die, or anvil, over which the peripheral portion of a disk is drawn, or formed, so that the 1 forming operation serves also as the cap-applying operation.

The improved method may be practiced in a suitable press. Such press is illustrated in the accompanying drawings, in which Fig. 1 represents a side elevational view of the press; Fig. 2, a plan sectional view taken as indicated at line 2 of Fig. 1; Fig. 3, an enlarged broken sectional view taken as indicated at line 33 of Fig. 2; and Fig. 4, an en? larged broken vertical sectional view of the capped carbon, the dotted lines showing the relation of the punching and forming die.

It may be stated, preliminarily, according to the preferred method, the carbons are located in suitable holders mounted in a carrier, or dial, this member having a step by step movement to bring the carbon successively into position to be capped; and a strip of brass, or the like, is fed beneath an annular punching and forming die which serves to punch the disks and then form the disks over the upper ends of the carbons, as they are successively presented beneath the die.

In the illustration given, A represents a .bedplate'secured to the base portion of a press and surrounded by a rotatable dial, or carrier. A; B designates a reciprocating cross-head with which the press is provided; G design ates means for rotating the dial in a step by step movement; and D designates means for feeding a strip D of brass, or other suitable material, through the press.

The dial,or carbon carrier, A, is provided wit-h an annular series of sockets, or holders, 1, which accommodate the carbons 2. The carrier A is mounted on a central journal 3. A block 4 which is recessed to accommodate one edge portion of the dial A has one end portion mounted on the plate A, and the other end portion secured to the upper end of the Serial No. 32,408.

journal 3. The block 4 is provided with an annular shearing die 5, above which is located a stripper 6. The plate A is provided with a guide post C which engages freely a perforation 8 with which the cross-head B is provided. The cross-head B is equipped with a locking pin 9 which is adapted to engage any pair of an annular series of sockets 10, with which the disk or dial, A, is provided. The cross-head B is fitted with an annular punch 11 which serves also the functions of a forming and capping tool. Through the central bore 12 or" the cross-head B, which registers with the bore through the punch 11, (3X- tends a rod 13 which is equipped at its lower end with a head, or flange, 13. This rod serves as an ejector for dislodging the capped carbon after it has been lifted from the lower die by the punch. As the cross-head B nears the upper end of its stroke, a suitably mounted lever let, which extends through a transverse opening 15 in the cross-head, serves to prevent further upward movement of the plunger 13, thus causing the plunger to eject the capped carbon. The free end of the lever 14: is adapted to enga 'e an adjustment set screw 16 carried by the Irame of the machine.

The device C, for effecting step by step rotation of the carrier A, may be of any desired construction and arrangement, the illustration showing conventionally a Geneva move ment for effecting actuation of the dial. Any suitable means may be employed for feeding the brass strip B through the press. In the illustration given, the lower rolls of suitable pairs of feed rollers are illustrated. Any desired means of feeding the strip may be employed.

. In the practice of the improved method by means of the machine illustrated, the brass strip D is given an intermittent feed through the press between the planes of the lower die 5 and the stripper 6; and the carrier A is intermittently actuated to bring a carbon to the capping position. As the cross-head B descends, locking studs 9 engage the locking sockets of the carrier A. Also, the punch 11 punches a disk in the brass strip and forces the disk downwardly through the die 5 and forms it over the upper end of the carbon 2. It is preferred to equip each carbon socket- 1 with a depressible sleeve l normally supported on a spring 1 confined between the plate A and an external flange with which the upper end of the sleeve is provided.-

The spring tends normally to hold the sleeve elevated so that its upper end is nearly flush with the upper surface of the carrier A;

. produce a downturned flange for embracing the upper end portion of the carbon. The

cap thus formed is designated 17. v

It will be noted that the outer circumferential corner. of the punch 11 serves to shear the metal at the upper end of the lower die 5, and then to force the disk through the die 5 whereupon the cap is formed within the bore of the annular punch. When the lower end of the punch encounters the upper end of the spring-held sleeve 1 the latter is caused to recede from its elevatediposition.

The lower ends of the carbons, in the illustration given, rest upon the upper surface of the bed-plate A. Crushing, or breaking, of the carbon is prevented, however, by the spring-held sleeve which envelopes the carbon. d

For purpose of simplicity, a press adapted to form and apply one cap at a time has been illustrated. However, it will be understood that, in practice, provision may be made for forming and applying any desirednumber of caps at one stroke of the press.-

The invention renders it possible to greatly reduce the cost of manufacturing capped carb'ons for dry battery purposes, as will be readily understood by those skilledin the art.

In the example shown and described, the

cap islformed by forcing the peripheral margin of the. disk downwardly over the carbon. It is obvious that as an alternativear-rangement, the carbon may be forced against the disk and thereby the disk may be forced into a suitable die to cause the cap to be formed on the end of the carbon. Indeed, the hollow' punch 11 may be regardedas a die into which the cap is forced by the carbon.

The foregoing detailed description has been given for clearness of understanding only, and no unnecessary limitationsshould be understood therefrom, but the appended claims should be construed as broadly as per},

missible, in view of the prior art.

which is in position for 'capp What I regard as new, and desire to secure by Letters Patent, is: p

1. The method of capping a carbon which comprises: punching from a strip of sheetmetal a disk by means of an annular punch, continuing the movement of said punch until it draws the disk into the form of a cap over the upper end of a suitably supported carbon, liftingthe capped carbon free from the lower die through themedium of said punch, and dislodging the capped carbon from the annular punch. V I

2. Apparatus of the character set forth comprising a carrier provided with a plurality of sockets, spring-held sleeves mounted in said sockets and adapted to hold carbon pencils, a lower die mounted above the path of said sleeves, strip-feeding means, and a reciprocating annular punch adapted to punch a disk from a metal strip, force it through the lower die and form it asa cap over the upper end of a carbon.

3. Apparatus for the purpose set forth comprising; a bedplate, a carrier pl'ate mounted thereon, means for giving said carrier-plate a step by step movement, a series of carbon-holding sleeves mounted in said carrier-plate, springs yieldingly supporting said sleeves, a lower die disposedabove the path of said sleeves, an annular. punch working through said lower die, and means for feeding a strip of material between said punch and lower die.

l. Apparatus for the purpose set forth comprising: a bed-plate, a rotary carrier journalled thereon and resting upon the upper surface of the bed-plate, saidfcarrier being provided with an annular series of openings extending therethrough, sleeves mounted in said openings and adapted to receive carbons with their lower ends resting on .said bed-plate, springs supporting said sleeves, a lower die disposed above the path of said sockets, means for feeding a strip of metal across the lower die, and an. annular punch adapted to punch a disk from the strip, force it through the lower die and form it as a cap on the upper end of the carbon GEORGE G. GUNDEBSON. 

